September 2011 - Devel - libvirt List Archives

[libvirt] [PATCH] Fix python error reporting for some storage operations
by Cole Robinson 07 Mar '25

07 Mar '25

In the python bindings, all vir* classes expect to be passed a virConnect object when instantiated. Before the storage stuff, these classes were only instantiated in virConnect methods, so the generator is hardcoded to pass 'self' as the connection instance to these classes. Problem is there are some methods that return pool or vol instances which aren't called from virConnect: you can lookup a storage volume's associated pool, and can lookup volumes from a pool. In these cases passing 'self' doesn't give the vir* instance a connection, so when it comes time to raise an exception crap hits the fan. Rather than rework the generator to accomodate this edge case, I just fixed the init functions for virStorage* to pull the associated connection out of the passed value if it's not a virConnect instance. Thanks, Cole diff --git a/python/generator.py b/python/generator.py index 01a17da..c706b19 100755 --- a/python/generator.py +++ b/python/generator.py @@ -962,8 +962,12 @@ def buildWrappers(): list = reference_keepers[classname] for ref in list: classes.write(" self.%s = None\n" % ref[1]) - if classname in [ "virDomain", "virNetwork", "virStoragePool", "virStorageVol" ]: + if classname in [ "virDomain", "virNetwork" ]: classes.write(" self._conn = conn\n") + elif classname in [ "virStorageVol", "virStoragePool" ]: + classes.write(" self._conn = conn\n" + \ + " if not isinstance(conn, virConnect):\n" + \ + " self._conn = conn._conn\n") classes.write(" if _obj != None:self._o = _obj;return\n") classes.write(" self._o = None\n\n"); destruct=None

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[libvirt] [PATCH] web docs -- macvtap mode explanation
by Stefan Berger 27 Oct '23

27 Oct '23

This adds more information about the different macvtap device modes. Regards, Stefan

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[libvirt] Supporting vhost-net and macvtap in libvirt for QEMU
by Anthony Liguori 27 Oct '23

27 Oct '23

Disclaimer: I am neither an SR-IOV nor a vhost-net expert, but I've CC'd people that are who can throw tomatoes at me for getting bits wrong :-) I wanted to start a discussion about supporting vhost-net in libvirt. vhost-net has not yet been merged into qemu but I expect it will be soon so it's a good time to start this discussion. There are two modes worth supporting for vhost-net in libvirt. The first mode is where vhost-net backs to a tun/tap device. This is behaves in very much the same way that -net tap behaves in qemu today. Basically, the difference is that the virtio backend is in the kernel instead of in qemu so there should be some performance improvement. Current, libvirt invokes qemu with -net tap,fd=X where X is an already open fd to a tun/tap device. I suspect that after we merge vhost-net, libvirt could support vhost-net in this mode by just doing -net vhost,fd=X. I think the only real question for libvirt is whether to provide a user visible switch to use vhost or to just always use vhost when it's available and it makes sense. Personally, I think the later makes sense. The more interesting invocation of vhost-net though is one where the vhost-net device backs directly to a physical network card. In this mode, vhost should get considerably better performance than the current implementation. I don't know the syntax yet, but I think it's reasonable to assume that it will look something like -net tap,dev=eth0. The effect will be that eth0 is dedicated to the guest. On most modern systems, there is a small number of network devices so this model is not all that useful except when dealing with SR-IOV adapters. In that case, each physical device can be exposed as many virtual devices (VFs). There are a few restrictions here though. The biggest is that currently, you can only change the number of VFs by reloading a kernel module so it's really a parameter that must be set at startup time. I think there are a few ways libvirt could support vhost-net in this second mode. The simplest would be to introduce a new tag similar to <source network='br0'>. In fact, if you probed the device type for the network parameter, you could probably do something like <source network='eth0'> and have it Just Work. Another model would be to have libvirt see an SR-IOV adapter as a network pool whereas it handled all of the VF management. Considering how inflexible SR-IOV is today, I'm not sure whether this is the best model. Has anyone put any more thought into this problem or how this should be modeled in libvirt? Michael, could you share your current thinking for -net syntax? -- Regards, Anthony Liguori

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[libvirt] [PATCH 0/4] Multiple problems with saving to block devices
by Daniel P. Berrange 24 Mar '13

24 Mar '13

This patch series makes it possible to save to a block device, instead of a plain file. There were multiple problems - WHen save failed, we might de-reference a NULL pointer - When save failed, we unlinked the device node !! - The approach of using >> to append, doesn't work with block devices - CGroups was blocking QEMU access to the block device when enabled One remaining problem is not in libvirt, but rather QEMU. The QEMU exec: based migration often fails to detect failure of the command and will thus hang forever attempting a migration that'll never succeed! Fortunately you can now work around this in libvirt using the virsh domjobabort command

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[libvirt] [PATCHv4 00/51] another round of snapshot patches
by Eric Blake 05 Nov '12

05 Nov '12

I think I've addressed most findings from round 3 - by implementing the ability to redefine a snapshot, it becomes possible to restore snapshot hierarchy when recreating a transient domain by the same name. New goodies in this round: several bug fixes, add virsh snapshot-edit, drop undefine --snapshots-full (you can only remove snapshot metadata on undefine). I tested as I went, but this went through so many rebases that there may be some nasties that snuck in; but I wanted to get this posted now. I also know that I'm missing at least one major feature requested in the v3 review: namely, transient domains _should_ auto-remove snapshot metadata files when they halt, but right now aren't doing that. v3 was at: https://www.redhat.com/archives/libvir-list/2011-August/msg01132.html Also available here: git fetch git://repo.or.cz/libvirt/ericb.git snapshot or browse online at: http://repo.or.cz/w/libvirt/ericb.git/shortlog/refs/heads/snapshot I'm also trying to group things by several bugzilla related to various patches (looks like I still need to create a few): Eric Blake (51): https://bugzilla.redhat.com/show_bug.cgi?id=674537 snapshot: fix corner case on OOM during creation https://bugzilla.redhat.com/show_bug.cgi?id=733762 snapshot: better events when starting paused snapshot: fine-tune ability to start paused snapshot: expose --running and --paused in virsh snapshot: fine-tune qemu saved images starting paused snapshot: improve reverting to qemu paused snapshots snapshot: properly revert qemu to offline snapshots snapshot: fine-tune qemu snapshot revert states no bug filed yet... should be one about no stale metadata snapshot: allow deletion of just snapshot metadata snapshot: add snapshot-list --parent to virsh https://bugzilla.redhat.com/show_bug.cgi?id=733529 snapshot: speed up snapshot location snapshot: avoid crash when deleting qemu snapshots snapshot: track current domain across deletion of children snapshot: simplify acting on just children no bug filed yet... should be one about no stale metadata snapshot: let qemu discard only snapshot metadata snapshot: identify which snapshots have metadata snapshot: reflect new dumpxml and list options in virsh snapshot: identify qemu snapshot roots snapshot: allow recreation of metadata snapshot: refactor virsh snapshot creation snapshot: improve virsh snapshot-create, add snapshot-edit snapshot: add qemu snapshot creation without metadata no bug filed yet... should be one about snapshot migration snapshot: add qemu snapshot redefine support snapshot: prevent stranding snapshot data on domain destruction snapshot: teach virsh about new undefine flags snapshot: refactor some qemu code snapshot: cache qemu-img location snapshot: support new undefine flags in qemu snapshot: prevent migration from stranding snapshot data https://bugzilla.redhat.com/show_bug.cgi?id=638510 snapshot: refactor domain xml output snapshot: allow full domain xml in snapshot snapshot: correctly escape generated xml snapshot: update rng to support full domain in xml snapshot: store qemu domain details in xml snapshot: additions to domain xml for disks snapshot: reject transient disks where code is not ready snapshot: introduce new deletion flag snapshot: expose new delete flag in virsh snapshot: allow halting after snapshot snapshot: expose halt-after-creation in virsh snapshot: wire up new qemu monitor command snapshot: support extra state in snapshots snapshot: add <disks> to snapshot xml snapshot: also support disks by path snapshot: add virsh domblklist command snapshot: add flag for requesting disk snapshot snapshot: wire up disk-only flag to snapshot-create snapshot: reject unimplemented disk snapshot features snapshot: make it possible to audit external snapshot snapshot: wire up live qemu disk snapshots snapshot: use SELinux and lock manager with external snapshots docs/formatdomain.html.in | 40 +- docs/formatsnapshot.html.in | 269 ++- docs/schemas/Makefile.am | 1 + docs/schemas/domain.rng | 2555 +------------------- docs/schemas/{domain.rng => domaincommon.rng} | 32 +- docs/schemas/domainsnapshot.rng | 84 +- examples/domain-events/events-c/event-test.c | 37 +- include/libvirt/libvirt.h.in | 66 +- src/conf/domain_audit.c | 12 +- src/conf/domain_audit.h | 4 +- src/conf/domain_conf.c | 902 ++++++-- src/conf/domain_conf.h | 76 +- src/esx/esx_driver.c | 38 +- src/libvirt.c | 256 ++- src/libvirt_private.syms | 8 + src/libxl/libxl_conf.c | 5 + src/libxl/libxl_driver.c | 11 +- src/qemu/qemu_command.c | 5 + src/qemu/qemu_conf.h | 1 + src/qemu/qemu_driver.c | 1532 +++++++++--- src/qemu/qemu_hotplug.c | 18 +- src/qemu/qemu_migration.c | 48 +- src/qemu/qemu_migration.h | 2 - src/qemu/qemu_monitor.c | 24 + src/qemu/qemu_monitor.h | 4 + src/qemu/qemu_monitor_json.c | 33 + src/qemu/qemu_monitor_json.h | 4 + src/qemu/qemu_monitor_text.c | 40 + src/qemu/qemu_monitor_text.h | 4 + src/qemu/qemu_process.c | 11 +- src/uml/uml_driver.c | 56 +- src/vbox/vbox_tmpl.c | 43 +- src/xen/xend_internal.c | 12 +- src/xenxs/xen_sxpr.c | 5 + src/xenxs/xen_xm.c | 5 + tests/domainsnapshotxml2xmlin/disk_snapshot.xml | 16 + tests/domainsnapshotxml2xmlout/disk_snapshot.xml | 77 + tests/domainsnapshotxml2xmlout/full_domain.xml | 35 + .../qemuxml2argv-disk-snapshot.args | 7 + .../qemuxml2argv-disk-snapshot.xml | 39 + .../qemuxml2argv-disk-transient.xml | 27 + tests/qemuxml2argvtest.c | 2 + tests/virsh-optparse | 20 + tools/virsh.c | 772 +++++- tools/virsh.pod | 214 ++- 45 files changed, 3978 insertions(+), 3474 deletions(-) copy docs/schemas/{domain.rng => domaincommon.rng} (98%) create mode 100644 tests/domainsnapshotxml2xmlin/disk_snapshot.xml create mode 100644 tests/domainsnapshotxml2xmlout/disk_snapshot.xml create mode 100644 tests/domainsnapshotxml2xmlout/full_domain.xml create mode 100644 tests/qemuxml2argvdata/qemuxml2argv-disk-snapshot.args create mode 100644 tests/qemuxml2argvdata/qemuxml2argv-disk-snapshot.xml create mode 100644 tests/qemuxml2argvdata/qemuxml2argv-disk-transient.xml -- 1.7.4.4

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[libvirt] I need help for use virDomainInterfaceStats
by Фёдор Пранович 03 Apr '12

03 Apr '12

Hi I want use the virDomainInterfaceStats for get statistic of domain, but I don't now how get path parametr. Please help me! Thanks.

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[libvirt] [PATCH 0/2] Introduce two new virsh commands
by Osier Yang 19 Dec '11

19 Dec '11

These two patches is to introduce two new virsh commands, one is eject-media, which is to eject media from CD or floppy drive, the other is insert-media, which is to insert media into CD or floppy drive. There are commands existed can be used to eject/insert media, such as "update-device", but it's not quite easy to use. That's the original intention of these patches. Both of the two commands only allow to operate on CDROM or floppy disk. [PATCH 1/2] virsh: Introduce two new commands to insert or eject media [PATCH 2/2] doc: Add docs for two new introduced commands Regards Osier

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[libvirt] [test-API][PATCH 1/2] Add support for spice graphics
by Nan Zhang 14 Dec '11

14 Dec '11

* utils/Python/xmlgenerator.py: This extends graphics element for spice XML composing, and support sub-elements settings for audio, images, streaming and so on: <graphics type='spice' autoport='yes'> <image compression='auto_glz'/> <jpeg compression='auto'/> <zlib compression='auto'/> <playback compression='on'/> <streaming mode='filter'/> <clipboard copypaste='no'/> </graphics> * utils/Python/xmlbuilder.py: Add 2 methods add_graphics() and build_graphics() to XmlBuilder class. --- utils/Python/xmlbuilder.py | 36 +++++++++++++++++++++++- utils/Python/xmlgenerator.py | 62 +++++++++++++++++++++++++++++++++++++---- 2 files changed, 91 insertions(+), 7 deletions(-) diff --git a/utils/Python/xmlbuilder.py b/utils/Python/xmlbuilder.py index 5a0f8c8..739eccb 100644 --- a/utils/Python/xmlbuilder.py +++ b/utils/Python/xmlbuilder.py @@ -64,6 +64,13 @@ class XmlBuilder: hostdev_node, domain.getElementsByTagName("console")[0]) return hostdev + def add_graphics(self, params, domain): + graphics = xmlgenerator.graphics_xml(params) + graphics_node = domain.importNode(graphics.childNodes[0], True) + domain.getElementsByTagName("devices")[0].insertBefore( + graphics_node, domain.getElementsByTagName("console")[0]) + return graphics + def build_domain_install(self, params): domain = xmlgenerator.domain_xml(params, True) self.add_disk(params, domain) @@ -151,6 +158,12 @@ class XmlBuilder: self.write_toxml(hostdev) return hostdev.toxml() + def build_graphics(self, params): + graphics = xmlgenerator.graphics_xml(params) + if __DEBUG__: + self.write_toxml(graphics) + return graphics.toxml() + def build_pool(self, params): pool = xmlgenerator.pool_xml(params) if __DEBUG__: @@ -242,6 +255,20 @@ if __name__ == "__main__": interfacexml = xmlobj.build_interface(params) + #-------------------------- + # get graphics xml string + #-------------------------- + print '=' * 30, 'graphics xml', '=' * 30 + params['graphtype'] = 'spice' + params['image'] = 'auto_glz' + params['jpeg'] = 'auto' + params['zlib'] = 'auto' + params['playback'] = 'on' + params['streaming'] = 'filter' + params['clipboard'] = 'no' + + graphicsxml = xmlobj.build_graphics(params) + #--------------------- # get pool xml string #--------------------- @@ -297,6 +324,13 @@ if __name__ == "__main__": params['memory'] = '1048576' params['vcpu'] = '2' params['inputbus'] = 'usb' + params['graphtype'] = 'spice' + params['image'] = 'auto_glz' + params['jpeg'] = 'auto' + params['zlib'] = 'auto' + params['playback'] = 'on' + params['streaming'] = 'filter' + params['clipboard'] = 'no' params['sound'] = 'ac97' params['bootcd'] = '/iso/rhel5.iso' @@ -367,7 +401,7 @@ if __name__ == "__main__": #---------------------------------------- # get domain snapshot xml string #---------------------------------------- - params['name'] = 'hello' + params['snapshotname'] = 'hello' params['description'] = 'hello snapshot' snapshot_xml = xmlobj.build_domain_snapshot(params) diff --git a/utils/Python/xmlgenerator.py b/utils/Python/xmlgenerator.py index d57dd33..460f2e5 100644 --- a/utils/Python/xmlgenerator.py +++ b/utils/Python/xmlgenerator.py @@ -233,12 +233,6 @@ def domain_xml(params, install = False): input_element.setAttribute('bus', 'ps2') devices_element.appendChild(input_element) - # <graphics> - graphics_element = domain.createElement('graphics') - graphics_element.setAttribute('type', 'vnc') - graphics_element.setAttribute('port', '-1') - graphics_element.setAttribute('keymap', 'en-us') - devices_element.appendChild(graphics_element) domain_element.appendChild(devices_element) # <sound> @@ -253,6 +247,62 @@ def domain_xml(params, install = False): return domain +def graphics_xml(params): + graphics = xml.dom.minidom.Document() + # <graphics> + graphics_element = graphics.createElement('graphics') + if not params.has_key('graphtype'): + params['graphtype'] == 'vnc' + + graphics_element.setAttribute('type', params['graphtype']) + graphics.appendChild(graphics_element) + + if params['graphtype'] == 'vnc': + graphics_element.setAttribute('port', '-1') + graphics_element.setAttribute('keymap', 'en-us') + elif params['graphtype'] == 'spice': + graphics_element.setAttribute('autoport', 'yes') + if params.has_key('image'): + image_element = graphics.createElement('image') + # image to set image compression (accepts + # auto_glz, auto_lz, quic, glz, lz, off) + image_element.setAttribute('compression', params['image']) + graphics_element.appendChild(image_element) + if params.has_key('jpeg'): + jpeg_element = graphics.createElement('jpeg') + # jpeg for JPEG compression for images over wan (accepts + # auto, never, always) + jpeg_element.setAttribute('compression', params['jpeg']) + graphics_element.appendChild(jpeg_element) + if params.has_key('zlib'): + zlib_element = graphics.createElement('zlib') + # zlib for configuring wan image compression (accepts + # auto, never, always) + zlib_element.setAttribute('compression', params['zlib']) + graphics_element.appendChild(zlib_element) + if params.has_key('playback'): + playback_element = graphics.createElement('playback') + # playback for enabling audio stream compression (accepts on or off) + playback_element.setAttribute('compression', params['playback']) + graphics_element.appendChild(playback_element) + if params.has_key('streaming'): + streaming_element = graphics.createElement('streaming') + # streamming for settings it's mode attribute to one of + # filter, all or off + streaming_element.setAttribute('mode', params['streaming']) + graphics_element.appendChild(streaming_element) + if params.has_key('clipboard'): + clipboard_element = graphics.createElement('clipboard') + # Copy & Paste functionality is enabled by default, and can + # be disabled by setting the copypaste property to no + clipboard_element.setAttribute('copypaste', params['clipboard']) + graphics_element.appendChild(clipboard_element) + else: + print 'Wrong graphics type was specified.' + sys.exit(1) + + return graphics + def disk_xml(params, cdrom = False): disk = xml.dom.minidom.Document() # <disk> -- START -- 1.7.4.4

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[libvirt] [PATCH 00/14] Add a virtlockd lock manager daemon
by Daniel P. Berrange 05 Dec '11

05 Dec '11

The lock manager infrastructure we recently added to QEMU only has two possible drivers at this time, 'nop' and 'sanlock'. The former does absolutely nothing, while the latter requires a 3rd party package installed and is a little heavy on disk I/O and storage requirements. This series adds a new daemon 'virtlockd' which is intended to be enabled by default on all hosts running 'libvirtd'. This daemon provides a service for disk locking based on the traditional fcntl() lock primitives. There is a new libvirt manager plugin which talks to this daemon over RPC. The reason for doing the locks in a separate process is that we want the locks to remain active, even if libvirtd crashes, or is restarted. The virtlockd daemon has this one single job so should be pretty reliable and selfcontained. This patch series really benefits from the new RPC APIs, requiring minimal code for the new daemon / client At this time, virtlockd does not lock the actual disk files, but instead creates a lockspace & leases under /var/lib/libvirt/lockd. The lockspace we use for disks is named org.libvirt.lockd.files, and lease names are based on a SHA256 checksum of the fully qualified disk name. eg /var/lib/libvirt/lockd/org.libvirt.lockd.files/adf94fc33a24da1abff7dd7374a9919bb51efee646da8c3ac464c10cd59750bd These leases are all zero-bytes long and no I/O is ever performed on them, only fcntl() is used. So there is material overhead. Whenever creating or deleting leases, we first acquire a lock on /var/lib/libvirt/lockd/org.libvirt.lockd.files/org.libvirt.lockd.index A non-root virtlockd will instead use $HOME/.libvirt/lockd By default we gain protection out of the box against - Starting two guests on the same host with the same disk image not marked with <shareable/> - libvirtd getting confused and forgetting a guest, allowing it to be started for a 2nd time If the admin mounts a shared filesytem (eg NFS) on /var/lib/libvirt/lockd then this protection is extended across all hosts sharing that mount volume. As part of this series, I also introduce support for systemd services for libvirtd and libvir-guests.

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[libvirt] [RFC PATCH 0/5] Support online resizing of block devices.
by Osier Yang 28 Nov '11

28 Nov '11

This patch series introduce new API "virDomainBlockResize" to expose qemu monitor command "block_size", which is for resizing the a block device while the domain is running. The prototype for the new API is: int virDomainBlockResize (virDomainPtr dom, const char *path, unsigned long long size, unsigned int flags) * "@path" is the absolute path of the block device, which can be extraced from domain xml. * The units for "@size" is kilobytes, which might be not quite properly. (qemu HMP uses Megabytes as the default units, QMP uses Bytes as the default units, so it means we need to divice "@size" by 1024 for HMP, and multiply "@size" by 1024 for QMP. On the other hand, we need to check the overflowing). Any ideas on this is welcomed. * "@flags" is unused currently. [PATCH 1/5] block_resize: Define the new API [PATCH 2/5] block_resize: Wire up the remote protocol [PATCH 3/5] block_resize: Implement qemu monitor functions [PATCH 4/5] block_resize: Implement qemu driver method [PATCH 5/5] block_resize: Expose the new API to virsh

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